THE ISG VIEWING WAND - AN APPLICATION TO ATLANTOAXIAL CERVICAL SURGERY USING THE LEFORT-I MAXILLARY OSTEOTOMY

Surgical access to the clivus and upper cervical spine may be facilita ted by a number of approaches. The Le Fort I maxillary osteotomy has b een described to give improved access to the skull base for removal of tumours' and treating vertebrobasilar aneurysms.(2'3) We describe a c ase in which the combination of a particularly high translocation of t he body of C2 and poor mouth opening had precluded a standard transora l approach by restricting access to the operative field, Anterior deco mpression of the body of C2 was therefore performed via a maxillary do wn-fracture with the aid of an interactive image guidance system, the ISG Viewing Wand.(4,5) The ISG Viewing Wand is a new intra-operative 3 dimensional (3D) image guidance system which has now been used in ove r three hundred neurosurgical cases at Frenchay Hospital, Bristol. We briefly discuss the principles of the viewing wand and describe its un ique application providing anatomical navigation in upper cervical spi ne surgery.